Rosgorgia inexspectata, new genus and species of Subergorgiidae (Cnidaria,Octocorallia) from off the Antarctic Peninsula

The family Subergorgiidae comprises two genera, Subergorgia with three spec ies and Annella with two species. All the previously known species are dist ributed in tropical and subtropical waters from the northern Red Sea to the central Pacific. The presence of a subergorgoiid in Antarctic waters could support the hypothesis that at least part of the Antarctic fauna has its o rigin in the Cretaceous period, when Antarctica was part of the Gondwana co ntinent. The new genus Rosgorgia with the new species inexspectata is place d in the family Subergorgiidae by the presence of smooth. fusiform and ofte n anastomosing needles in the axis, wart spindles in the coenenchyme. and c oelenteric cavities of polyps only present rn the coenenchyme. The genus Ro sgorgia differs from Subergorgia and Annella by the presence of tuberculate rods in the axis. It is further distinguished from Annella by the absence of double-disk sclerites in the coenenchyme, and not anastomosing branches.